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.\"     from: @(#)biff.1	6.5 (Berkeley) 3/14/91
.\"	$Id: biff.1,v 1.14 2000/04/13 01:55:56 dholland Exp $
.\"
.Dd July 31, 1999
.Dt BIFF 1
.Os "Linux NetKit (0.17-pre-20000412)"
.Sh NAME
.Nm biff
.Nd "be notified if mail arrives and who it is from"
.Sh SYNOPSIS
.Nm biff
.Op Cm ny
.Sh DESCRIPTION
.Nm Biff
informs the system whether you want to be notified when mail arrives
during the current terminal session.
.Pp
Options supported by
.Nm biff :
.Bl -tag -width 4n
.It Cm n
Disables notification.
.It Cm y
Enables notification.
.El
.Pp
When mail notification is enabled, the header and first few lines of
the message will be printed on your screen whenever mail arrives.
A
.Dq Li biff y
command is often included in the file
.Pa \&.login
or
.Pa \&.profile
to be executed at each login.
.Pp
.Nm Biff
operates asynchronously via the
.Xr comsat 8
service. If that service is not enabled,
.Nm biff
will not do anything. In that case, or for synchronous notification,
use the
.Ar MAIL
variable of
.Xr sh 1
or the
.Ar mail
variable of
.Xr csh 1 .
.Sh SEE ALSO
.Xr csh 1 ,
.Xr mail 1 ,
.Xr sh 1 ,
.Xr comsat 8
.Sh HISTORY
The
.Nm
command appeared in 
.Bx 4.0 .
.Sh BUGS
.Xr su 1 ,
and biff don't seem to get on too well. This is probably due to the tty 
still being owned by the person using su. This can result in 
.Dq Li Permission denied 
messages when attempting to change the biff status of your session.
.Pp 
Please report bugs to netbug@ftp.uk.linux.org including diffs/patches,
compiler error logs or as complete a bug report as is possible.
